Non-Spore-Forming Gram-Positive Bacilli. Corynebacterium C. diphtheriae Disease Diphteria Opportunistic infections by other Corynebacterium species (dipheroids). Properties. Club-shaped also V- or L-shaped Beaded appearance Methachromatic granules (Albert staining) Nonmotile
Opportunistic infections by other Corynebacterium species (dipheroids)
Incubation period of 2–5 days.
Sore throat, fever, Enlargement of neck lymph nodes and neck edema. Irregulatory of cardiac rhythm, difficulties with vision, speech and swallowing.
Corrosion of myelin sheaths in the central and peripheral nervous system leading to degenerating motor control
(a secondary infection)
A glycolipid inhibits eukaryotic cell oxidation.
Removes N-acetyl nuraminic acid from musine membranes.
BExotoxin(Encoded by gen tox from a temperate phage)
Fragment B. Binding of the toxin
Fragment A. Enzymatic activity
Reaction with EF2
I. Cause inflammation (4-7 days later): No antitoxin in patient
II. No inflammation: Antitoxin is present (Immune person)
a tellurite plate
20000-100000 unit (Intra muscular)
A combination of diphtheria toxoid, tetanus toxoid, and killed pertusis organism.
Given at 2, 4 an 6 months of age, with a booster at 1 and 6 years of age and then each 10 years afterward. (DPT or DT)
The toxoid is prepared by treating the exotoxin with 0.3% formaldehyde.
Endogenously from gasterointestinal tract.
Inducing actin polymerization in cytoplasm
Release from phagolysosome
Blood and CSF samples on blood agar
Colonies: Small, gray colonies with a narrow zone of beta hemolysis
Resistant are rare
B. antheracis, B.cereus
C. tetani, C. botulinum, C. perfringens, C. difficile
Anthrax (common in animal but rare in humans).
No resistant strain isolated
Rare infections: Meningitis, Osteomyelitis, …
Spores on grains survive during steaming and rapid frying. Spore germinated when rice is kept warm.
Portal of entry is the gastrointestinal tract.
A short incubation period (4 hours) with nausea and vomiting similar to staphylococcal food poisoning.
Involves a long incubation period (18 hours) with diarrhea and resembles clostridial gastroenteritis.
No antibiotic is given. Only symptomatic treatment
Grains (specially rice) should not be reheated
An aerobic bacteria
Spores are widespread in soil.
The portal of entry is a wound site.
Germination of spores is favoured by necrotic tissue and poor blood supply in the wound.
It is carried intra-axonally (retrograde) to the central nervous system, where it binds to ganglioside receptors and blocks release of inhibitory mediators (e.g. glycine, Gamma-aminobutiric acid) at spinal synapses leading to hyper reflection and spastic paralysis.
1. Wound should be cleaned and debrided.
2. Tetanus toxoid booster should be given.
3. Tetanus immune globulin should be given.
4. Penicillin administered.
Observing from the gut ---> Carrying via the blood to peripheral nerve synapses ---> Blocking release of acetylcholine ---> Paralysis
Wounds should be debrided
Incubation: 8-16 hours, then watery diarrhea with cramps and little vomiting. Resolves in 24 hours.
It is a part of normal flora of gasterointestinal tract (3%)